problems with exploit please help

Hello I have been using the memory card exploit from this website http://www.i-hacked.com/content/view/94/62/ .I was able to successfully complete my first memory card exploit and it works now my problem is that I am trying to do another Hd loader exploit but,I get the all the steps completed and installation complete on the memory card and then when I try to load the ps1 disc it starts the game not the exploit.can anybody help me thanks